Some women are upset that Kylie Jenner has a flat stomach just 1 month after giving birth

Kylie Jenner made her grand return to Instagram on Thursday, sharing the first full photos of daughter Stormi Webster. With a slideshow of two pictures that featured the 20-year-old makeup mogul posing and cradling her 1-month-old baby girl, Jenner caused quite a stir about her parenting journey thus far. But aside from how she’s handling her role as a mother, fans seem super invested in how the reality star has bounced back into shape.

Just before sharing photos of Stormi in a cute bunny onesie, Jenner took to Snapchat and Instagram stories to show off her post-baby body. According to critics on social media, her flat and toned stomach seems too good to be true. However, women’s health expert Dr. Jennifer Wider says it’s not.

“Each woman is different — her labor and delivery is different and her postpartum recovery is different, and depends on many, many factors,” Wider explains to Yahoo Lifestyle. “In the case of Kylie Jenner, she is 20 years old; it is her first pregnancy, and she was in excellent physical shape before and during her pregnancy. Also, unlike the average American woman, she probably has a team of experts helping her: nutritionists, chefs, workout trainers. This can speed the recovery process along as well.”

After considering the exceptional circumstances of the lip kit mogul’s pregnancy, fans have come to understand that Jenner must have some help taking care of the baby and taking care of herself. But Wider says her ability to so quickly return to sharing sexy mirror selfies also has a lot to do with her age.

“Younger women tend to have an easier time bouncing back to their pre-pregnancy bodies for several reasons,” says Wider. “Younger skin tends to be more resilient than older women’s skin. And if the skin hasn’t been stretched in subsequent pregnancies, it helps a lot too. Younger women tend to have a faster metabolism in the late teens, early 20s, so they can burn calories faster than older women, which results in quicker and faster weight loss.”

For model Behati Prinsloo, who showed off her post-baby body just two weeks after giving birth to her second daughter, Gio, the natural metabolism and shape that a woman is in are important factors in postpartum weight loss. In addition, the 28-year-old Victoria’s Secret model previously told Yahoo Lifestyle that she breastfed her first-born, Dusty, which Wider says aids in weight loss right after delivery.

Behati Prinsloo also took to Instagram Stories to show off her body just two weeks after giving birth. (Photo: Instagram/behatiprinsloo)

As for Jenner, it hasn’t yet been confirmed whether the new mother is breastfeeding or not. But her post-baby journey will continue to be different from those of other women — just as various pregnancies are.

“There are so many factors at play here,” Wider concludes, “and they differ between women.”